The present invention relates to a shrinkage-free sealing structure of a heat pipe, and more particular, to a method which seals one open end of a heat pipe without performing shrinkage process thereof.
For the majority of electronic products, the performance depends on the operation processing speed, while the heat dissipation is a consequence of the operation processing speed. In the example of a central processing unit (CPU) of a computer motherboard, transmission of various command signals and calculation program parameters are performed with very high speed to generate significant heat. The heat adversely affects the performance and reduces the operation speed of the central processing unit. The operation may even be halted when the central processing unit is over heated. Therefore, heat dissipation devices are required to keep the electronic products working under a tolerable temperature range to avoid interruption or termination of operation.
To enhance heat dissipation efficiency, highly thermal conductive heat pipes operative to absorb and dissipate heat efficiency have been used in the heat dissipation devices. A heat pipe is in the form of a tube with one closed end and one open end. A wick structure is installed in the heat pipe and a working fluid is introduced into the heat pipe, followed by the process of sealing the open end. When the heat pipe is in contact with the electronic products, the heat absorbing end absorbs the heat from the electronic products, such that a phase transition from the liquid state to the gas state occurs to the working fluid. After flowing to the cooling end of the heat pipe, the gaseous working fluid is then condensed back to the liquid state and re-flows back to the heat absorbing end by the capillary effect provided by the wick structure. Therefore, the circulation and phase transition of the working fluid irritated in the heat pipe provides enhanced heat dissipation performance, such that the electronic product can always operate under a uniform and working temperature
To ensure the quality and functionality of the heat pipe, the sealed end of the heat pipe is further subject to a soldering process. As shown in FIG. 1, the conventional sealing structure of a heat pipe is performed by shrinking the open end portion of the heat pipe 10a into a shrunk end portion 100a, and a sealing module is used to clamp the terminus of the shrunk end portion 100a, such that a flattened region 101a is formed. The edge of the flattened region 101a is then soldered to ensure a air-tight sealing effect.
However, the objective for shrinking the end portion 10a into the shrunk end portion 100a is to decrease the volume and area of the sealing structure, such that it is advantageous for the subsequent soldering process. However, as the shape of the wick structure proximal to the shrunk end portion 10a is unstable, the working fluid has to be filled manually. Therefore, the fabrication process is laborious and costly. The wick structure installed and the working fluid filled after the shrunk end portion 100a is formed will become very difficult.
To resolve the problems caused by the conventional heat pipe structure as described above, the Applicant, with many years of experience in this field, has developed a shrinkage-free sealing structure of heat pipe as described as follows